A low power continuous time hysteresis comparator with an average current consumption of 614nA at 1.5 voltage

This paper proposes a low-power continuous time comparator with hysteresis for low speed and low power applications, such as duty cycle temperature sensors. A minimum current selector with hysteresis is proposed to reduce the bias current of the comparator when the differential input is large, and increase the bias current when the differential input is small, thereby converting the static bias current of the comparator into dynamic bias current to reduce power consumption. In addition, the increased hysteresis path makes the output of the comparator highly immune to disturbances. Furthermore, chopper is typically added to suppress 1/f noise and DC offset, and the comparator designed in this article combines chopper with hysteresis. The comparator is fabricated in 110nm CMOS technology, works under a 1.5V supply voltage, and has a average current of 530nA.